- inevitably (adv.)
- mid-15c., from inevitable + -ly (2).
- inexact (adj.)
- 1828, from in- (1) "not, opposite of" + exact. Related: Inexactly.
- inexactitude (n.)
- 1786, from in- (1) "not, opposite of" + exactitude.
- inexcusable (adj.)
- early 15c., from Latin inexcusabilis, from in- "not, opposite of" (see in- (1)) + excusabilis, from excusare (see excuse). Related: Inexcusably.
- inexhaustible (adj.)
- c.1600, from in- (1) "not, opposite of" + exhaustible (see exhaust). Related: Inexhaustibly.
- inexorable (adj.)
- 1550s, from Middle French inexorable and directly from Latin inexorabilis "that cannot be moved by entreaty," from in- "not, opposite of" (see in- (1)) + exorabilis "able to be entreated," from exorare "to prevail upon," from ex- "out" (see ex-) + orare "pray" (see orator). Related: Inexorably; inexorability.
- inexpedient (adj.)
- c.1600, from in- (1) "not, opposite of" + expedient. Related: Inexpedience; inexpediently.
- inexpensive (adj.)
- 1837 (implied in inexpensively), from in- (1) "not, opposite of" + expensive.
- inexperience (n.)
- 1590s, from French inexpérience (mid-15c.), from Late Latin inexperientia, from in- "not, opposite of" (see in- (1)) + experientia (see experience).
- inexperienced (adj.)
- 1620s, adjective from inexperience.
- inexpert (adj.)
- mid-15c., from in- (1) "not, opposite of" + expert (adj.), or else from Old French inexpert, from Latin inexpertus "without experience, unpracticed." Related: Inexpertly.
- inexpiable (adj.)
- 1560s, from Latin inexpiabilis "that cannot be atoned for," from in- "not" (see in- (1)) + expiabilis, from expiare (see expiation).
- inexplicable (adj.)
- early 15c., from Middle French inexplicable or directly from Latin inexplicabilis "that cannot be unfolded or disentangled, very intricate," figuratively, "inexplicable," from in- "not, opposite of" (see in- (1)) + explicabilis "that may be explained" (see explicable). Related: Inexplicably.
- inexplicit (adj.)
- 1775 (implied in inexplicitly), from in- (1) "not, opposite of" + explicit. Or else from Latin inexplicitus "not to be unfolded; unexplained." Related: Inexplicitly; inexplicitness.
- inexpressible (adj.)
- 1620s, from in- (1) "not" + expressible (see express (v.)). Related: Inexpressibly.
- inexpugnable (adj.)
- late 15c., from Latin inexpugnabilis "not to be taken by assault," from in- "not" (see in- (1) + expuglabilis, from expugnare (see expugn).
- inextinguishable (adj.)
- c.1500, from in- (2) "not" + extinguishable (see extinguish). Related: Inextinguishably; inextinguishability.
- inextricable (adj.)
- early 15c., from Latin inextricabilis "that cannot be disentangled," from in- "not, opposite of" (see in- (1)) + extricare (see extricate). Related: Inextricably.
- Inez
- fem. proper name, Spanish form of Agnes (q.v.).
- infallibility (n.)
- 1610s, from Medieval Latin infallibilitas, from infallibilis (see infallible).
- infallible (adj.)
- early 15c., from Medieval Latin infallibilis, from in- "not, opposite of" (see in- (1)) + Late Latin fallibilis (see fallible). In reference to Popes, attested from 1870. Related: Infallibly.
- infamous (adj.)
- late 14c., from Medieval Latin infamosus, from Latin in- "not, opposite of" (see in- (1)) + famosus "celebrated" (see famous). Meaning influenced by Latin infamis "of ill fame" (see infamy). As a legal term, "disqualified from certain rights of citizens in consequence of conviction of certain crimes" (late 14c.). Related: Infamously.
- infamy (n.)
- early 15c., from Old French infamie (14c.), earlier infame, and directly from Latin infamia "ill fame, bad repute, dishonor, from infamis "of ill fame," from in- "not, without" + fama "reputation" (see fame (n.)).
- infancy (n.)
- late 14c., from Anglo-French enfaunce and directly from Latin infantia "early childhood," literally "inability to speak," from infantem (see infant).
- infant (n.)
- late 14c., "child during earliest period of life" (sometimes extended to age 7 and sometimes including a fetus), from Latin infantem (nominative infans) "young child, babe in arms," noun use of adjective meaning "not able to speak," from in- "not, opposite of" (see in- (1)) + fans, present participle of fari "speak" (see fame (n.)). As an adjective, 1580s, from the noun.
- Infanta (n.)
- "daughter of a king of Spain or Portugal," c.1600, from Spanish and Portuguese infanta, fem. of infante, from Latin infantem (see infant).
- infanticide (n.)
- 1650s, "the killing of infants;" 1670s, "one who kills an infant," from infant + -cide.
- infantile (adj.)
- mid-15c., "pertaining to infants," from Latin infantilis "pertaining to an infant," from infans (see infant). Sense of "infant-like" is from 1772.
- infantilism (n.)
- 1894 in a psychological sense; see infantile + -ism. Earlier in a physiological sense, "retarded and imperfect physical development."
- infantry (n.)
- 1570s, from French infantrie, from older Italian, Spanish infanteria "foot soldiers, force composed of those too inexperienced or low in rank for cavalry," from infante "foot soldier," originally "a youth," from Latin infantem (see infant). Meaning "infants collectively" is recorded from 1610s.
- infantryman (n.)
- 1837, from infantry + man (n.).
- infarct (n.)
- 1873, from medical Latin infarctus (Latin infartus), past participle of infarcire "to stuff into," from in- + farcire “to stuff” (see farce).
- infarction (n.)
- 1680s, noun of action from Latin infarcire (see infarct).
- infatigable (adj.)
- c.1500, from French infatigable (15c.), from Latin infatigabilis, from in- "not, opposite of" (see in- (1)) + fatigabilis, from fatigare "to weary" (see fatigue).
- infatuate (v.)
- 1530s, "turn (something) to foolishness, frustrate," from Latin infatuatus, past participle of infatuare "make a fool of," from in- "in" (see in- (2)) + fatuus "foolish." Specific sense of "inspire (in someone) a foolish romantic passion" is from 1620s. Related: Infatuated; infatuating.
- infatuation (n.)
- 1640s, noun of action from infatuate, or else from French infatuation or directly from Late Latin infatuationem (nominative infatuatio), from past participle stem of infatuare.
- infeasibility (n.)
- 1650s, from infeasible + -ity.
- infeasible (adj.)
- 1530s, from in- (1) "not, opposite of" + feasible.
- infect (v.)
- late 14c., from Latin infectus, past participle of inficere "to spoil, stain," literally "to put in to, dip into," from in- "in" (see in- (2)) + facere "perform" (see factitious). Related: Infected; infecting.
- infection (n.)
- late 14c., "infectious disease; contaminated condition;" from Old French infeccion "contamination, poisoning" (13c.) and directly from Late Latin infectionem (nominative infectio), noun of action from past participle stem of Latin inficere (see infect). Meaning "communication of disease by agency of air or water" (distinguished from contagion, which is body-to-body communication), is from 1540s.
- infectious (adj.)
- "catching, having the quality of spreading from person to person," 1540s of diseases, 1610s of emotions, actions, etc.; see infect + -ous.
- infective (adj.)
- late 14c., from Latin infectivus, from infectus (see infect).
- infelicitous (adj.)
- 1754, from in- (1) "not, opposite of" + felicitous. Related: infelicitously.
- infelicity (n.)
- late 14c., from Latin infelicitas "ill luck, misfortune," from infelix (genitive infelicis) "unfruitful, barren; unfortunate, unhappy, causing misfortune, unlucky," from in- "not, opposite of" (see in- (1)) + felix (see felicity).
- infer (v.)
- 1520s, from Latin inferre "bring into, carry in; deduce, infer, conclude, draw an inference; bring against," from in- "in" (see in- (2)) + ferre "carry, bear," from PIE *bher- (1) "to bear, to carry, to take" (cf. Sanskrit bharati "carries;" Avestan baraiti "carries;" Old Persian barantiy "they carry;" Armenian berem "I carry;" Greek pherein "to carry;" Old Irish beru/berim "I catch, I bring forth;" Gothic bairan "to carry;" Old English and Old High German beran, Old Norse bera "barrow;" Old Church Slavonic birati "to take;" Russian brat' "to take," bremya "a burden"). Sense of "draw a conclusion" is first attested 1520s.
- inference (n.)
- 1590s, from Medieval Latin inferentia, from Latin inferentem (nominative inferens), present participle of inferre (see infer).
- inferential (adj.)
- 1650s, from Medieval Latin inferentia (see inference) + adj. suffix -al (1).
- inferior (adj.)
- early 15c., of land, "low, lower," from Latin inferior "lower, further down" (also used figuratively), comparative of inferus (adj.) "that is below or beneath," from infra "below" (see infra-). Meaning "lower in degree, rank, or importance" is from 1530s; also in an absolute sense, "of low quality or rank."
- inferior (n.)
- "person inferior to another in rank, etc.," early 15c., from inferior (adj.).
- inferiority (n.)
- 1590s, probably from Medieval Latin *inferioritas; see inferior + -ity. Inferiority complex first attested 1922.
The surrender of life is nothing to sinking down into acknowledgment of inferiority. [John C. Calhoun]